As an airbag apparatus for protecting a passenger, there is, for example, one disclosed in U.S. Pat. No. 5,586,782 or one disclosed in Japanese Patent Application Laid-Open No. 8-207689.
The former, namely an airbag apparatus for lateral collision (DUAL PRESSURE SIDE IMPACT AIRBAG) disclosed in U.S. Pat. No. 5,586,782, is configured such that, at a time of a lateral collision of an automobile, an electrical signal is transmitted to an inflator via a harness for ignition when the collision is detected, gas generated from the inflator ignited is introduced from a gas discharging hole into an airbag folded to be accommodated within a case body in a backrest in an ordinary situation of the automobile to expand the same, the expanded airbag presses and opens a lid of the case body, and the airbag is spread between a passenger and a passenger compartment side wall, so that an impact generated when the passenger secondarily collides against the passenger compartment side wall is absorbed by the airbag.
The airbag is structured such that a bag body formed in a generally L-shaped configuration with a head protecting portion and a chest protecting portion is divided into a gas passage to the head protecting portion and a gas passage to the chest protecting portion by a dividing plate or a sewn portion, and the gas discharged from the inflator is filled into the respective protecting portions in a short time.
Also, the latter, namely an airbag for lateral collision disclosed in Japanese Patent Application Laid-Open No. 08-207689, is structured such that an airbag is folded and accommodated within a backrest in an ordinary situation of an automobile, like the former, and at a time of a lateral collision of an automobile the airbag is abruptly expanded by discharged gas rapidly from an inflator into the airbag via a supporting pipe so that an impact generated when a passenger secondarily collides against a passenger compartment side wall is absorbed by the airbag.
However, in a structure of such a conventional airbag apparatus, as the inflator (the former) or the supporting pipe (the latter) is housed in the airbag of the airbag apparatus from an opening portion thereof, there is a risk that an inner face of the airbag may be injured by friction between the airbag and an edge portion of the inflator or a holder for holding the inflator inside the airbag.
Also, the gas discharged from the inflator tends to concentrate on the vicinity of an inflator-mounting portion positioned at the opening portion of the airbag, which is required to be improved.
The present invention has been achieved in view of the problems in such a conventional art, and an object thereof is to provide an airbag apparatus which prevents the friction between the airbag and the edge portion of the inflator or the holder for holding the inflator inside the airbag and the injury of the airbag due to a high temperature gas discharged from the inflator.